1. Field of the Invention
The present invention relates to an ink jet recording apparatus and in particular to such an ink jet recording apparatus having a construction in which heat generated by a driver circuit that outputs a drive signal used to eject a droplet of ink is radiated by a heat sink.
2. Related Art Statement
Patent Document 1 (Japanese Patent Application Publication P2002-240306 or its corresponding U.S. Pat. No. 6,679,595B2) or Patent Document 2 (Japanese Patent Application Publication P2003-080793 or its corresponding U.S. Patent Application Publication No. 2003-063449A1) discloses an ink jet recording apparatus including two recording heads that eject droplets of ink and cooperate with each other to record an image on a recording medium. Each of the recording heads includes a plurality of ink ejection nozzles arranged in an array; a cavity unit that has a plurality of pressure chambers corresponding to the ink ejection nozzles, respectively, and has a generally rectangular, stacked structure; and a piezoelectric actuator unit that is stacked on, and adhered to, the cavity unit and has a plurality of piezoelectric actuators (i.e., a plurality of pressure changing devices) corresponding to the pressure chambers, respectively. The ink jet recording apparatus additionally includes two flexible flat cables (i.e., two flexible wiring cables) which are stacked on the respective piezoelectric actuator units of the two recording heads and each of which has a plurality of electric wirings that are electrically connected to the piezoelectric actuators of the piezoelectric actuator unit of a corresponding one of the two recording heads.
Two IC chips (i.e., two driver circuits) each of which outputs a drive signal to a corresponding one of the two recording heads so as to eject a droplet of ink from an arbitrary one of the ink ejection nozzles of the one recording head, are provided on the two flexible flat cables, respectively. The two flexible flat cables extend in a same direction parallel to the direction in which the respective arrays of ink ejection nozzles of the two recording heads extend. Thus, the two IC chips are located adjacent each other. In addition, the two IC chips contact a common heat sink, which radiates the heat generated by the chips.